Method of and a device for making drain pipes



Feb. 4, 1964 JUUSELA ETAL 3,120,107

METHOD OF AND A DEVICE FOR MAKING DRAIN PIPES Filed Nov. 30. 1959 2Sheets-Sheetl FIG 2 M W V H' l I 53 \5 Tanel/ Juuse/a and Lari Juu'sa/aFIG 4 ATTORN EYS METHOD OF AND A DEVICE FOR MAKING DRAIN PIPES I FiledNov. 30. 1959 Feb. 4, 1964 T. JUUSELA ETAL 2 Sheets-Sheet 2.

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FIG 8 Tana/i Juuse/a and Lari Juuse/a l NVE NTOR S BY 1 M Poi/ Z AT TORN EYS United States Patent 3,129,1597 PVTETHGD 6F AND A EEVECE FORMAKHNG DRAHI This invention relates to draining and more particularly toa method of and a device for making drain pipes by passing a ribbon fedfrom a drum into an underground hole in which the ribbon is brought toform a continuous drain.

According to the invention the method of making drain pipes comprisingthe steps of bending a ribbon fed from a drum as to bring the ribbonedge portions to overlap each other as to form a pipe with a smallerdiameter than the final drain pipe is intended to have and feeding saidpipe into an underground hole, whe e the pipe is allowed to expand incorrespondence with the diameter of said hole, whereby a split jointbetween the longitudinal, mutually overlapping edges of the pipe ismaintained.

According to an especially favourable embodiment of the invention saidsplit is situated in an upright position when the drain pipe is arrangedwithin the hole in the ground.

By making the drain pipes by the method according to the inventionseveral important advantages are achieved compared with drain pipes madeby known methods. Because the split joint is maintained between thelongitudinal, overlapping edges of the drain pipe at special valveefiect is obtained which promotes the draining of the surroundingground. This split joint which according to the invention is preferablyarranged in a vertical position when the drain pipe is located in theearth also provides a special filtering eliect preventing mineral earthparticles heavier than water from penetrating into the drain pipe wherethey form deposits preventing the flowing of w ter. The drain pipe isproduced by this method in a very simple way. No special steps arenecessary to prevent mineral earth particles from entering into thepipe, so as is the case for instance at draining tiles, where the tilesmust be protected with a surrounding layer of gravel.

Further features of the invention will appear from the followingdescription referring to the drawings.

The device for carrying out the method comprises a displacing bodyarranged at the lower end of a knife adapted to cut the ground. it hasforming tube arranged behind said knife and provided with a funnel atits upper end, into which the ribbon from the drum is led. Said funnelis adapted to form the pipe and it extends, curved backwards, into thehole formed behind the displacing body.

By the device according to the invention the drain pipe may be formedrapidly and in a very simple way, whereby the costs of production andmounting become highly reduced.

The invention will be described more in detail with reference to theaccompanying drawings, which diagrammatically show one embodiment of adevice for carrying out the method of the invention.

FIGURE 1 is a side elevation view, partly in section, of the rear partof the device.

FIGURE 2 is an end elevation of the device shown in FIG. 1.

FIGURE 3 is a section taken on line lll-lll of PEG. 1.

FIGURE 4 is a longitudinal axial section of the mole plug on the lowerend of the device.

FIGURES 5 and 6 are cross sections of the drain pipe in position in theground; and

3,120,107 Patented Feb. 4, 1964 FIGS. 7 and 8 are sectional and sideelevation views, respectively, of a modified form of drain pipe.

The device shown in FIGS. 1 and 2, a so-called mole plow, is providedwith a knife extending downwards from the frame, the front edge of theknife being sharpened as shown in FIG. 3. The extension of the back partof the knife is for ld by two shields 2 spaced at a distance smallerthan the thickness of the knife. In the lower end of the knife there isa mole plug 3 forming the underground hole for the drain pipe. Betweenthe shields behind the knife there is arranged a forming tube 5 providedat its upper end with a funnel 4 the tube 5 having a vertical portion 5awith a cross section oval in form. The forming tube has a lower and rearend 512 curving downwardly and rearwardly from the lower end of verticalportion 5a and forming an extension of the displacing body, the crosssection of the lower and rear end gradually changing from oval to round.The ribbon 6 forming the drain pipe is rolled on a drum 3 supported by astand on the frame.

The drain pipe is formed according to the invention by means or" theabove described mole plow in the following way: The ribbon 6 is fed fromthe drum 8 over a smaller wheel 8a into the funnel 4, whereby the edgeportions of the ribbon will overlap each other. Said smaller wheel is aquite common expedient. ts use is not necessary. It is easily possibleto arrange the drum 8 in such a way that the ribbons run directly intothe funnel 4'. Consequentl said smaller wheel forms no part of theinstant invention. Having passed the funnel the overlapping of the edgeportions increases when the ribbon enters the oval forming tube 5 insuch a way that the ribbon forms a pipe 9 as shown in TI 3. Where thepipe passes through the curved lower portion of the forming tube thecross section of which gradually increases to a round form the pipewhich in the inlet end of the tube is bent to an oval form withconsiderably overlapping edge portions can owing to its elasticityexpand and partly straighten out, whereby the cross section of the pipeincreases and its form becomes round. In the outlet end of the formingtube which is arranged to form an extension of the mole plug 3 the pipereaches substantially its final size and shape which it will have whenremaining in the hole after being removed from the forming tube. Thefunnel and the forming tube 5 are arranged to cooperate with each otherand with the ribbon in such a way that the overlapping of the edges ofthe ribbon when it is bent to form a tube is at the side of the drawingpipe when the drain pipe is placed in the mole hole behind the outletend of the forming tube 5. The overlapping edges are arranged in such away that the outer edge extends downwardly and the inner edge upwardly.Between the edges is a vertical split joint 1% maintained as illustratedin FIGS. 5 and 6. Said vertical split joint is adapted to permit waterentrance into the drain pipe. The said position of the edges of theribbon prevents earth from penetrating into the split joint and closingit.

The particular position of the drum 8 relative the forming tube 5 is acritical feature of the invention. It is of decisive importance that theoverlapping of the ribbon edges in the aforedescribed is at the side ofthe drain pipe when it is laid in the mole hole. This is obtained byarranging the axis of the drum 3 parallel to the moving direction of themole plow as shown in FIGS. 1 and 2. The oval shape of the forming tube5 makes it easier to transport the tube through the space in the earthcut by the knife 1. The circular lower end and outlet of the formingtube facilitates the shaping of the drain. pipe according to the molehole.

in FIGS. 5 and 6 there is shown how the split joint 10 provides aspecially favourable valve effect. FIG. 5 represents the situation whenthe pressure inside the drain pipe is greater than the pressure actingoutside the pipe. In FIG. 6 the inside pressure is smaller. The splitjoint 10 is formed by the overlappingedge portions 11 and 12 of thedrain pipe. In the situation shown in FIG. these edge portions 11 and 12contact each other at a and b, whereby thewater inside the drain pipe isprevented from escaping through the split joint. In FIG. 6 there is nocontact bet seen the edge portions 11 and '12. The water may dueto anincreasing external pressure flow more and more easily through the splitjoint into the drain pipe and be removed through the pipe. The drainpipe according to the invention is capable'of automatically regulatingthe flow of water through the split joint under varying conditions.

The drain pipe maypreferably be made so that the longitudinal splitjoint is directed in such a way relative to the pipe, that the'edge 13ofthe outer edge portion 11 of the drain pipe will be positioned nearthe lower part of 'the drain pipe and the edge 14 of the inner edgeportion 'means, whereby the formation of deposits the drain pipereducing the flow of water along the pipe may be prevented.

The ribbon used for forming the drain pipe may be either perforated ornot and it can be cut into suitable portions or consist of a continuousribbon. The marginal portions of the ribbon may also have offsetportions, e.g. corrugated, as shown in FIGS. 7 and 8 so that between theoverlapping edge portions of the final pipe there remains a sufiicientsplit for the flow of water into the pipe. The marginal inner portion ofthe drain pipe may also have a wave-like form or the like to providesufficient splits permitting Water to flow into the pipe.

7 For carrying out the method according to the invention preferablyplastic ribbons are used. Such a plastic ribbon meets all requirementsconcerning elasticity, stalbility, strength, etc. Ribbon-s of othermaterials with similar favourable properties may of course also be usedsuccessfully. Such materials are e.g. fibrous cellulose, fibrouslignine, aluminium and similar materials. The ribbon forming the drainpipe may consist either Wholly of such a material or of a material incombination with plastic. In the last mentioned case the material may bemixed in a plastic composition or a ribbon of this mate rial may be e.g.coated with a layer of plastic. The ribbon forming the drain pipe mayalso consist of some other material with suitable properties, whichmaterial e.g. is impregnated before use.

. It is obvious that various changes may he made without departing fromthe scope of the invention, the particular embodiment being describedmerely to illustrate the invention. If it is preferred to provide thedrain pipe with two split joints the drain pipe may thus be formed oftwo halves of pipes or two separate ribbons.

What we claim is:

V 1. A method of producing and laying 'a drain pipe, in which a moleplow having a hole torrning plug disposed below a cutting knife isforced through the ground for forming a substantially cylindrical borefor receiving the drain pipe, said drain pipe'being formed by a flexibleflat strip which is unwound from a supply drum carried on the plow abovethe level of the ground to be drained together with the device by whichthe mole is produced,

said method comprising the step of bending said strip material into avertical tubular form above the level of 4 the ground with the outeredge extending forwardly of the plow and the inner ed e extendingrearwardly, bending the flexible strip, when forming the pipe, into across section smaller than that of the mole hole, by overlapping theedges of the flexible strip and leaving them in an unsecured conditionand making the said overlapping sufficiently great that it will bema'mtained even after the strip material has been allowed to expand dterthe pipe has been deposited within the mole hole, laying the thus formedtube by curving it downwardly and rearwardly of the plow into the molehole through the space out by the knife carrying V the mole plow withoutany longitudinal movement between .the drain pipe and the mole hole, andpositioning said unsecured overlapping edges of the strip with the outeredge extending downwardly and the inner edge extending upwardly to forma downwardly opening vertical slit along one side of the drain pipe.

2. A method as claimed in claim 1 in which the flat strip is a ribbon,the marginal portions of which have otiset portions, whereby saidmarginal portions are spaced from each other when they are overlapped.

3. A method as claimed in claim 1 inwhioh the flat strip is a ribbonhaving one marginal portion fiat and l the other marginal portion havingoiiset portions, whereby said margina portions are spaced from eachother when they are overlapped.

4. A machine for forming a laying drain pipe, comprising a mole plowwith a knife and a mole plug on the bottom of said knife, a supply drummounted on said mole plow for holding a roll of flexible resilient pipeforming material, the axis of said drum being parallel to the said moleplug, and a pipe forming tube vertically mounted on said plow above thepoint on said mole plow which is adapted to be at the ground level, saidtube having a vertical portion with an oval cross section and beingadapted to receive the strip of pipe forming material from said supplydrum and bend it into a pipe with the edges 7 of said strip overlappedat a portion of said tube on one side of said mole plow, said pipeiorming tube having a lower and rear end extending downwardly and thencurving rearwardly of said mole plow from the lower end of the ovalcross section vertical portion of said pipe torm- 7 ing tube and havingthe rear end substantially aligned with said mole plug and having across section which is oval at the point where it joins the lower end ofsaid vertical portion and said cross section changing to circular at itsrear end, whereby the strip of pipe forming material can be passed intothe vertical portion of said pipe forming tube with the edges overlappedto form an oval pipe and the thus formed pipe is transferred downwardlyand rearwardly through the circular rear end and into the hole bored inthe ground by the mole plug as the mole plow moves through the ground.

5. A machine as claimed in claim 4 in which the bore of said lower andrear portion is smaller in cross section than the cross section of themole plug.

' References Cited in the file of this patent UNITED STATES PATENTS330,556 Briggs Nov. 17, 1885 516,750 Blaine Mar. 20,1894 1,006,116 MorseOct. 17, 1911 1,340,836 Powell May 18, 19-20 1,819,426 Ladd Aug. 18,1931 1,904,666 Sack Apr. 18, 1933 2,314,045 Johnson Mar. 16, 1943FOREIGN PATENTS 283,035 Great Britain Jan. 5, 1928 OTHER REFERENCESAgricultural Engineering, vol. 39, No. 11, November 1958, p. 712.

1. A METHOD OF PRODUCING AND LAYING A DRAIN PIPE, IN WHICH A MOLE PLOWHAVING A HOLE FORMING PLUG DISPOSED BELOW A CUTTING KNIFE IS FORCEDTHROUGH THE GROUND FOR FORMING A SUBSTANTIALLY CYLINDRICAL BORE FORRECEIVING THE DRAIN PIPE, SAID DRAIN PIPE BEING FORMED BY A FLEXIBLEFLAT STRIP WHICH IS UNWOUND FROM A SUPPLY DRUM CARRIED ON THE PLOW ABOVETHE LEVEL OF THE GROUND TO BE DRAINED TOGETHER WITH THE DEVICE BY WHICHTHE MOLE IS PRODUCED, SAID METHOD COMPRISING THE STEP OF BENDING SAIDSTRIP MATERIAL INTO A VERTICAL TUBULAR FORM ABOVE THE LEVEL OF THEGROUND WITH THE OUTER EDGE EXTENDING FORWARDLY OF THE PLOW AND THE INNEREDGE EXTENDING REARWARDLY, BENDING THE FLEXIBLE STRIP, WHEN FORMING THEPIPE, INTO A CROSS SECTION SMALLER THAN THAT OF THE MOLE HOLE, BYOVERLAPPING THE EDGES OF THE FLEXIBLE STRIP AND LEAVING THEM IN ANUNSECURED CONDITION AND MAKING THE SAID OVERLAPPING SUFFICIENTLY GREATTHAT IT WILL BE MAINTAINED EVEN AFTER THE STRIP MATERIAL HAS BEENALLOWED TO EXPAND AFTER THE PIPE HAS BEEN DEPOSITED WITHIN THE MOLEHOLE, LAYING THE THUS FORMED TUBE BY CURVING IT DOWNWARDLY ANDREARWARDLY OF THE PLOW INTO THE MOLE HOLE THROUGH THE SPACE CUT BY THEKNIFE CARRYING THE MOLE PLOW WITHOUT ANY LONGITUDINAL MOVEMENT BETWEENTHE DRAIN PIPE AND THE MOLE HOLE, AND POSITIONING SAID UNSECUREDOVERLAPPING EDGES OF THE STRIP WITH THE OUTER EDGE EXTENDING DOWNWARDLYAND THE INNER EDGE EXTENDING UPWARDLY TO FORM A DOWNWARDLY OPENINGVERTICAL SLIT ALONG ONE SIDE OF THE DRAIN PIPE.